1. Field of the Invention
The present invention relates to a shortening oil which contains diglycerides in a high concentration and a food fried with the shortening oil.
2. Discussion of the Background
It is becoming clear that diglycerides have a function of being less likely to become body fat (See JP-A 4-300826). In order to ingest diglycerides in an effective amount through daily foods processed with fats, it is necessary to produce a fat-processed food containing diglycerides in a high concentration.
On the other hand, the fats used in conventional shortenings for frying are non-blended fats such as soybean oil, rapeseed oil, corn oil, palm oil, coconut oil, and lard and fractions obtained from natural fats in order to be suitable for individual applications. However, fats having a high degree of unsaturation have poor storage stability and thus pose a problem that snack cakes produced with the fats develop an odor of deteriorated fats. Although fats based on palm oil or hydrogenated oils have frequently been used in order to prevent fat deterioration during storage, these fats have the problem that the fats based on palm oil taste too light and are poor in flavor, while the hydrogenated oils tend to emit an odor changed by hydrogenation upon heating.
In the production of friedcakes such as potato chips, the deep frying process reduces the water contained in starch for a short time to thereby cause the fried product to be crispy. However, such friedcakes have a problem that even slight moisture absorption reduces the crispness and considerably impairs the flavor. French fried potatoes and fried chicken also can be made to exhibit crispness by reducing the water content of the surface layer of the coating in the deep frying process. However, when the coating surface layer absorbs moisture even slightly, these fried foods also have reduced crispness and impaired flavor.
Furthermore, deep-fried foods such as friedcakes, french fried potatoes, fried chicken, and doughnuts often give off or ooze oil, giving not only poor appearance but losing crispness in the mouth, and being sticky.
U.S. Pat. No. 4,976,984 and EP-A 525,915 disclose edible fats containing phospholipids and diglycerides. However, there is no description therein concerning the deep frying process using an edible fat containing diglycerides in a high concentration. Moreover, shortening containing phospholipids has a problem that it discolors upon heating.